Species: Passerculus sandwichensis

Arrive on the breeding grounds between late March and early May, and begin nesting in May (George 1952, Baird 1968, Lein 1968, Maher 1973, Welsh 1975, Bedard and LaPointe 1984b, Wheelwright and Rising 1993). In North Dakota, breed from late May through late July, with peak breeding occurring from early June to mid-July (Stewart 1975). If the first nesting attempt fails, will renest, and many females produce a second clutch after a successful first nest (George 1952, Lein 1968, Taber 1968, Wiens 1969, Weatherhead 1979, Wheelwright and Rising 1993). In northern areas, may be limited to a single brood (Maher 1973, Weatherhead 1979). <br><br>In Saskatchewan, departed from breeding territories in early August, but remained in the area, foraging in weedy fields, along road edges, and along the margins of lakes and sloughs (Lein 1968). Fall migration occurs in mid- to late September (George 1952, Maher 1973). <br><br>In the Canadian Maritimes, male and female are philopatric (Bedard and LaPointe 1984b, Wheelwright and Rising 1993). Philopatry to breeding territories in Newfoundland is high; 95 percent of surviving males and 90 percent of surviving females return to within 40 meters of territories from a previous year (Wheelwright and Rising 1993). There is no information on philopatry in the Great Plains, and philopatry of grassland birds in the Great Plains may be low (Wiens 1974, Johnson 1996). Polygyny is common in populations residing in the Canadian Maritimes, but populations in other portions of the species range are generally monogamous (Welsh 1975, Wheelwright and Rising 1993).